1. Field
Aspects of the present disclosure relate generally to wireless communications, and more particularly to managing interference in wireless networks.
2. Background
Wireless communication networks are widely deployed to provide various communication services such as telephony, video, data, messaging, broadcasts, and so on. Such networks, which are usually multiple access networks, support communications for multiple users by sharing the available network resources. One example of such a network is the UMTS Terrestrial Radio Access Network (UTRAN). The UTRAN is the radio access network (RAN) defined as a part of the Universal Mobile Telecommunications System (UMTS), a third, generation (3G) mobile phone technology supported by the 3rd Generation Partnership Project (3GPP). The UMTS, which is the successor to Global System for Mobile Communications (GSM) technologies, currently supports various air interface standards, such as Wideband-Code Division Multiple Access (W-CDMA), Time Division-Code Division Multiple Access (TD-CDMA), and Time Division-Synchronous Code Division Multiple Access (TD-SCDMA). The UMTS also supports enhanced 3G data communications protocols, such as High Speed Packet Access (HSPA), which provides higher data transfer speeds and capacity to associated UMTS networks.
Generally, wireless multiple-access communication systems may simultaneously support communication for multiple mobile devices. Each mobile device may communicate with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from base stations to mobile devices, and the reverse link (or uplink) refers to the communication link from mobile devices to base stations. Further, communications between mobile devices and base stations may be established via single-input single-output (SISO) systems, multiple-input single-output (MISO) systems, multiple-input multiple-output (MIMO) systems, and so forth.
To supplement conventional base stations, low power base stations, for example, femto cells, pico cells, etc. can be deployed to provide more robust wireless coverage to mobile devices. As deployment of such base stations is unplanned, such low power base stations can interfere with communications of other base stations and/or UEs when base stations are deployed within a close vicinity of one another. Such interference can result in poor network performance and/or stability, for example, low up link (UL) rate for user equipment (UE).
For example, uplink interference and/or network performance are typically managed by controlling the UL rates of UEs. The existing approaches monitor the rise over thermal (ROT) parameters to make decisions about the UL rate control at the UE. ROT is the ratio of the received signal power to the thermal noise, and generally a reliable indicator of overall interference level and the system stability for macro networks that have geometric regularity and support handoffs. However, uplink interference control algorithms generally tailored for macro cells may yield less than desired network performance when small cells, for example, femtocells, pico cells, etc. are introduced into the network along macro cells as some of the geometric regularity and handoff assumptions are no longer valid.
Uplink power control mechanisms generally balance user quality of service (QoS) against interference caused to other links. The existing utility based uplink interference management and/or power control algorithms may require exchanging of information between base stations either directly or through the user equipment (UEs). However, the proposed mechanisms do not define the information to be exchanged and/or and how it must be used. As such, a mechanism for managing interference at a base station by defining information to be exchanged and how it is used may be desired.